update

backend/generator.py

@@ -0,0 +1,147 @@
+import asyncio
+import tempfile
+from datetime import datetime, timezone
+from pathlib import Path
+
+from config import (
+    CLAUDE_CLI,
+    DOC_DIR,
+    GENERATION_TIMEOUTS,
+    MAX_CONCURRENT_GENERATIONS,
+    STORAGE_DIR,
+)
+from database import update_guide
+
+_semaphore = asyncio.Semaphore(MAX_CONCURRENT_GENERATIONS)
+_active_processes: dict[str, asyncio.subprocess.Process] = {}
+
+
+async def cancel_guide(guide_id: str) -> bool:
+    process = _active_processes.get(guide_id)
+    if process and process.returncode is None:
+        process.kill()
+        now = datetime.now(timezone.utc).isoformat()
+        await update_guide(guide_id, status="error", progress=None, error_msg="Abgebrochen", updated_at=now)
+        return True
+    return False
+
+
+def _build_prompt(topic: str, format_name: str, html_path: Path, pdf_path: Path) -> str:
+    spec = (DOC_DIR / "Format" / f"{format_name}.md").read_text(encoding="utf-8")
+    reference = (DOC_DIR / "Referenz" / f"{format_name}.md").read_text(encoding="utf-8")
+
+    return f"""Erstelle einen Lern-Guide zum Thema "{topic}" im Format "{format_name}".
+
+Recherchiere zuerst die aktuelle Version und aktuelle Fakten zu "{topic}" per Websuche, damit Versionsnummern und Angaben stimmen.
+
+Schreibe die HTML-Datei nach: {html_path}
+Erstelle die PDF-Datei nach: {pdf_path}
+
+FORMAT-SPEZIFIKATION:
+{spec}
+
+REFERENZ-IMPLEMENTIERUNG (Stil-Vorlage, adaptiere für "{topic}"):
+{reference}
+"""
+
+
+async def _set_progress(guide_id: str, progress: str) -> None:
+    now = datetime.now(timezone.utc).isoformat()
+    await update_guide(guide_id, progress=progress, updated_at=now)
+
+
+async def _watch_files(guide_id: str, html_path: Path, pdf_path: Path, stop_event: asyncio.Event) -> None:
+    html_seen = False
+    pdf_mtime = 0.0
+    iteration = 0
+
+    while not stop_event.is_set():
+        await asyncio.sleep(2)
+
+        if not html_seen and html_path.exists():
+            html_seen = True
+            await _set_progress(guide_id, "HTML generiert…")
+
+        if pdf_path.exists():
+            current_mtime = pdf_path.stat().st_mtime
+            if current_mtime > pdf_mtime:
+                pdf_mtime = current_mtime
+                iteration += 1
+                await _set_progress(guide_id, f"Iteration {iteration}…")
+
+
+async def generate_guide(guide_id: str, topic: str, format_name: str) -> None:
+    async with _semaphore:
+        now = datetime.now(timezone.utc).isoformat()
+        await update_guide(guide_id, status="generating", progress="Lesen…", updated_at=now)
+
+        html_path = STORAGE_DIR / "html" / f"{guide_id}.html"
+        pdf_path = STORAGE_DIR / "pdf" / f"{guide_id}.pdf"
+
+        prompt = _build_prompt(topic, format_name, html_path, pdf_path)
+        await _set_progress(guide_id, "Generiere HTML…")
+
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".txt", delete=False, encoding="utf-8") as f:
+            f.write(prompt)
+            prompt_file = f.name
+
+        stop_event = asyncio.Event()
+        watcher = asyncio.create_task(_watch_files(guide_id, html_path, pdf_path, stop_event))
+
+        try:
+            timeout = GENERATION_TIMEOUTS.get(format_name, 600)
+            process = await asyncio.create_subprocess_exec(
+                CLAUDE_CLI,
+                "-p",
+                "--allowedTools", "Write,Bash,Read,WebSearch,WebFetch",
+                "--dangerously-skip-permissions",
+                stdin=asyncio.subprocess.PIPE,
+                stdout=asyncio.subprocess.PIPE,
+                stderr=asyncio.subprocess.PIPE,
+            )
+            _active_processes[guide_id] = process
+            stdout, stderr = await asyncio.wait_for(
+                process.communicate(input=prompt.encode("utf-8")),
+                timeout=timeout,
+            )
+
+            stop_event.set()
+            await watcher
+
+            now = datetime.now(timezone.utc).isoformat()
+
+            if process.returncode != 0:
+                error = stderr.decode("utf-8", errors="replace")[:2000]
+                await update_guide(guide_id, status="error", progress=None, error_msg=error, updated_at=now)
+                return
+
+            if not html_path.exists():
+                await update_guide(guide_id, status="error", progress=None, error_msg="HTML-Datei wurde nicht erstellt", updated_at=now)
+                return
+
+            if not pdf_path.exists():
+                await update_guide(guide_id, status="error", progress=None, error_msg="PDF-Datei wurde nicht erstellt", updated_at=now)
+                return
+
+            await update_guide(
+                guide_id,
+                status="done",
+                progress=None,
+                html_path=str(html_path),
+                pdf_path=str(pdf_path),
+                updated_at=now,
+            )
+
+        except asyncio.TimeoutError:
+            stop_event.set()
+            await watcher
+            now = datetime.now(timezone.utc).isoformat()
+            await update_guide(guide_id, status="error", progress=None, error_msg=f"Timeout nach {timeout}s", updated_at=now)
+        except Exception as e:
+            stop_event.set()
+            await watcher
+            now = datetime.now(timezone.utc).isoformat()
+            await update_guide(guide_id, status="error", progress=None, error_msg=str(e)[:2000], updated_at=now)
+        finally:
+            _active_processes.pop(guide_id, None)
+            Path(prompt_file).unlink(missing_ok=True)